NMR, DTA, and impedance spectroscopy studies of ion mobility, phase transitions, and ionic conductivity in K1-x (NH4) (x) SbF4 crystals

作者：Kavun V Ya^*; Uvarov N F; Zemnukhova L A; Ulikhin A S; Didenko N A; Brovkina O V; Sergienko V I

来源：Russian Journal of Electrochemistry, 2013, 49(7): 633-644.

DOI：10.1134/S1023193513070069

• potassium-ammonium tetrafluoroantimonates(III)
• ion mobility
• phase transitions
• conductivity
• NMR spectra

The ion mobility, phase transitions, and ionic conductivity in the crystal phases in the KF-NH4F-SbF3 system were studied by NMR, DTA, and impedance spectroscopy. An analysis of the F-19 and H-1 NMR spectra showed how the character of ionic motions in the fluoride and proton sublattices changed with temperature. The types and temperature ranges of ionic motions were determined. Diffusion of the fluoride and partially ammonium ions was found to be the dominant form of ionic motion in the high-temperature modifications formed as a result of phase transitions. According to the electrophysical data, the high-temperature K1 - x (NH4) (x) SbF4 phases (0.05 a parts per thousand currency sign x a parts per thousand currency sign 0.75) are superionic, their conductivity reaching similar to 10(-2)-10(-3) S/cm at 450-500 K.

• 出版日期2013-7